METABOLIC ACTIVITY OF NERVOUS SYSTEM 



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prising uniformity of non-protein nitrogen in the entire brain of 

 the albino rat. Although the average values for the non-protein 

 nitrogen content thus agree in both the control and test rats, 

 yet the successive differences during the twenty-four hours after 

 feeding are not at all similar, but the test rats show an interesting 

 deviation from the controls. This deviation, or the difference 

 between control and test rats, is well brought out by a graphic 

 representation (chart 1). 



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Chart 1 Showing the differences in the amount of non-protein nitrogen in 

 the brain of test rats from that found in the controls. 



From chart 1 we see clearly that the amount of non-protein 

 nitrogen in the test animal increases very rapidly at first, and 

 so far as the present data show, it reaches its maximum within 

 two hours after feeding. This high content of non-protein 

 nitrogen in the test brain soon begins to diminish, however, and 

 within the next five or six hours the content reaches the original 

 level found in the brain of the controls. 



The diminution of the non-protein nitrogen in the test rats 

 still*continues steadily, and at eight or nine hours after feeding 

 reaches a minimum, showing just as great a difference — in the 



